Chronic arterial insufficiency

Question 1

What proportion of patients with PVD are symptomatic?

Answer 1

25%

Question 2

Name the 2 conditions associated with chronic lower limb ischaemia

Answer 2

Intermittent claudication

Critical limb ischaemia

Question 3

What is the underlying cause of intermittent claudication and critical limb ischaemia?

Answer 3

Atherosclerosis

Question 4

Name 5 risk factors for peripheral vascular disease

Answer 4

Smoking (9x)
Hypertension (3x)
Diabetes mellitus (4x)
Hyperlipidaemia
Age
FHx
CAD or CVD

Question 5

Define intermittent claudication

Answer 5

Muscle pain of the lower limb on walking exercise, that is relieved by a short period of rest. Onset of symptoms >2 weeks.

Question 6

Where does intermittent claudication most commonly manifest?

Answer 6

Calf muscles

Question 7

Outline the prognosis of intermittent claudication

Answer 7

1/3 improve
1/3 remain stable
1/3 deteriorate

4% require intervention
2% result in amputation

Question 8

Name 3 differentials for intermittent claudication

Answer 8

Spinal stenosis
OA (esp hip)
Sciatica
Musculoligamentous strain
Popliteal artery entrapment (rare)

Question 9

Name the vessels affected in intermittent claudication

Answer 9

Superficial femoral artery (80%)
Aorto-iliac arteries (15%)
Calf arteries (5%)

Question 10

What are the 3 presentations of intermittent claudication?

Answer 10

Calf claudication (80%)
Calf, thigh, and buttock claudication (18%)
Leriche’s syndrome (2%)

Question 11

What is Leriche’s syndrome?

Answer 11

Aorto-Iliac occlusion disease.

A chronic lower limb ischaemia characterised by:

• Bilateral buttock claudication
• Erectile dysfunction
• Absent femoral pulses

Question 12

Describe the illness course of intermittent claudication

Answer 12

80% show no progression over 5 years.

After 5yr, 11% who smoke undergo amputation.

Question 13

What is the impact of smoking on intermittent claudication outcome?

Answer 13

After 5 years, 11% of smokers with claudication will undergo amputation. Compared to 0% who stop smoking.

Smoking also increases mortality.

Question 14

What is the impact of diabetes on intermittent claudication outcome?

Answer 14

Amputation rate over 5 years in 4x that of non-diabetics.

Increased risk of bypass failure.

Question 15

What investigations should be ordered in intermittent claudication?

Answer 15

FBC
BM
Serum lipids and cholesterol
Ankle/brachial pressure index
Exercise test

Duplex ultrasound: to all people for whom revascularisation is being considered.

Question 16

What is the role of full blood count in intermittent claudication management?

Answer 16

Assess the presence of anaemia, as it can aggravate vascular disease.

Question 17

What results of Ankle/brachial pressure index indicate normality and arterial disease?

Answer 17

Normal >1.1

Arterial disease <0.9

Question 18

Outline the treatment of intermittent claudication

Answer 18

Risk factor modification
Angioplasty and stent
Surgical bypass or graft

Question 19

What are the indications for surgical intervention of intermittent claudication?

Answer 19

Short distance claudication
Severe lifestyle limitation
Failure/unsuitable for endovascular treatment in aorto-iliac arteries

Question 20

What pharmacological treatments should patients with intermittent claudication be given?

Answer 20

20mg Atorvastatin (80mg in secondary prevention)
Daily Clopidogrel (300mg loading, 75mg), or
Aspirin (75mg)
If T2DM: metformin

Question 21

What non-pharmacological intervention is beneficial for intermittent claudication?

Answer 21

Supervised exercise programme: 2hr/wk for 3 months. Encourage to exercise to point of maximal pain.

Otherwise, 30min 3-5x per week until onset of symptoms.

Improves walking technique and capillary perfusion. Optimises collateral blood distribution.

Question 22

Define critical limb ischaemia

Answer 22

Rest pain for >2wk that is not relieved by simple analgesia, OR
Doppler ankle pressure <50mmHg

+/-

Tissue necrosis (ulceration or gangrene)

Question 23

How does the diagnostic criteria for critical limb ischaemia differ in diabetics?

Answer 23

Toe pressure <30mmHg if diabetic

Question 24

Describe the clinical features of critical limb ischaemia

Answer 24

Rest pain is worse at night and during elevation of limb.

This is relieved by hanging the limb.

Question 25

How does critical limb ischaemia appear on examination?

Answer 25

Cold | Sunset foot - due to compensatory vasodilation

Question 26

Describe Buerger's test and its indication

Answer 26

Used to test the adequacy of arterial supply to the legs. 1. Whilst supine, elevate the patient's legs 45 degrees for 1-2min. 2. Patient sit at end of bed with legs dangling. Ischaemia will show as pallor when elevated, and dark red when dangled due to reactive hyperaemia. The poorer the supply, the less elevation required for pallor.

Question 27

What investigations should be ordered in critical limb ischaemia?

Answer 27

``` Identify all arterial stenoses using: Colour duplex Doppler USS Angiography Magnetic resonance angiogram (MRA) CT angiogram (CTA) ```

Question 28

Describe the management of critical limb ischaemia

Answer 28

Revascularise where possible, starting proximally. Urgent referral to vascular team Optimise medical management (nursing care, analgesia) Angioplasty + stent (proximal) Bypass surgery or graft (distal) Amputation

Question 29

How does the aetiology differ between intermittent claudication and critical limb ischaemia?

Answer 29

Intermittent claudication usually results from single-level atherosclerosis. Critical limb ischaemia usually results from two-level atherosclerosis.

Question 30

Outline the Fontaine classification of lower limb ischaemia

Answer 30

``` Clinical classification of Peripheral artery disease: I. Asymptomatic II. Intermittent claudication III. Rest pain IV. Ulcers/gangrene ``` Critical limb ischaemia = Grades III and IV

Question 31

What are the features of diabetic foot?

Answer 31

Ulceration Infection (cellulitis, abscess, osteomyelitis) Sensory neuropathy Failure to heal trivial injuries

Question 32

Name 4 risk factors for ulceration in diabetic foot

Answer 32

``` Previous ulceration Neuropathy (stocking distribution and Charcot foot) Peripheral arterial disease - frequently highly calcified Altered foot shape Callus - high foot pressures Visual impairment Living alone Renal impairment ```

Question 33

What are the causes of ulceration in diabetic foot?

Answer 33

Neuropathy (45%) Ischaemia of large or small vessels (10%) Mixed neuropathic-ischaemic origin (45%)

Question 34

Describe the presentation of diabetic foot with pure neuropathic ulceration

Answer 34

Warm foot with palpable pulses Ulceration at pressure points Evidence of sensory loss ➔ unrecognised repeated trauma Normal or high duplex USS flow

Question 35

Describe the presentation of diabetic foot with ischaemic or mixed ulceration

Answer 35

Foot may be cool Absent pulses Ulcers commonly on toes, heel, metatarsal Secondary infection with minimal pus and mild cellulitis ABPIs may be misleadingly high due to calcification (diabetes) Low duplex USS flow

Question 36

What investigations can be used to differentiate the causes of diabetic foot ulceration?

Answer 36

Ankle/brachial pressure index Duplex USS Angiography - suspected critical limb ischaemia

Question 37

Outline prophylactic management of ulceration in diabetic foot

Answer 37

``` Specialist diabetes foot clinic with MDT Regular foot inspection Wide-fitting footwear Nail care with chiropody Debridement of calluses Keep foot cool Avoid walking barefoot ```

Question 38

Outline management of infection in established ischaemic ulceration

Answer 38

Treat local or systemic infection following trust ABX guidelines Debride/amputate any necrotic tissue Drain pus X-ray for osteomyelitis

Question 39

What surgical options are available for diabetic foot?

Answer 39

Angioplasty Femoro-distal bypass graft Amputation

Question 40

What surgical considerations must be made for diabetic patients?

Answer 40

Renal disease: close monitoring of hydration, BP and eGFR Metformin stopped 48hr prior to angiography due to risk of lactic acidosis T1DM require sliding scale when NBM Elevate legs to avoid pressure sores Prompt attention to any skin breaks

Question 41

What infections may occur in poorly managed ulcerations of diabetic foot?

Answer 41

Deep tissue infections - plantar abscess | Osteomyelitis

Question 42

What is the management of osteomyelitis of the toe or metatarsal?

Answer 42

Ray excision - surgical removal of toe and metatarsal

Question 43

What may cause the ABPI reading to be erroneously elevated?

Answer 43

Calcification of arteries - seen in diabetes